Gas turbine rotors with a configuration including a plurality of disks are known. In the disks, a plurality of through-holes extending in the direction parallel to the axis of the rotor are formed in the circumferential direction of the rotor. The disks are fastened together by spindle bolts and nuts. In such a rotor, a cavity for attaching nuts is formed (for example, see Patent Document 1).
Even greater efficiency is desired for gas turbines. In gas turbines, for example, elimination of even the minute windage loss generated when the rotor rotates is demanded.
Patent Document 1 describes a structure in which the working fluid is prevented from flowing inside the cavity by disposing a seal member fixed by a spindle bolt in the cavity. Specifically, this structure reduces windage loss by reducing the amount of working fluid flowing into the cavity and consequently enhances the efficiency of the gas turbine.